Mbed-https: Unable to resolve https-address

Mbed OS
16

I tried this code:

    SocketAddress sockAddr;
    connect_status = NSAPI_ERROR_OK;
    int index = 0;
    while(connect_status == NSAPI_ERROR_OK) {
        connect_status = network->get_dns_server(index++, &sockAddr, "st0");
        if ((connect_status == NSAPI_ERROR_OK) || (index == 1)) {
            switch (sockAddr.get_ip_version()) {
                case NSAPI_IPv4: printf("[NWKH] DNS #%d IPv4: ", index); break;
                case NSAPI_IPv6: printf("[NWKH] DNS #%d IPv6: ", index); break;
                default: printf ("[NWKH] DNS #%d IPv unknown: ", index);
            }

            (connect_status == NSAPI_ERROR_OK) ? printf(" %s:%d\n", sockAddr.get_ip_address(), sockAddr.get_port()) : printf("get DNS err: %d\n", connect_status);
        }
    }

And sockAddr.get_port() is always 0. Can someone confirm this? Shouldn’t this be the typical DNS port 53?

My problem still is that line 62 of mbed-http - Fork of SandBox’s original mbed-http (https://os… | Mbed fails with error -3009. Any ideas where to start debugging?

Edit:

I changed NetworkInterface::gethostbyname to this:

nsapi_error_t NetworkInterface::gethostbyname(const char *name, SocketAddress *address, nsapi_version_t version, const char *interface_name)

{

    printf("STACK NAME: %s\r\n", typeid(get_stack()).name());

    return get_stack()->gethostbyname(name, address, version, interface_name);

}

with the result P12NetworkStack. After grep-ing for this name I only get entries in .map-files so it looks to me like this is some kind of binary-blob which is linked at compile time? But where is the source-code?
Can I switch the network-stack?

Edit: Okay, I think I found the solution thanks to this post: Gethostbyname() question - Mbed OS - Arm Mbed OS support forum

network->gethostbyname(_parsed_url->host(), &address, NSAPI_IPv4, "st0");

Notice the two additional parameters at the end.